nikon 50mm f1.4

[AllanC]

hi all. had my 1.4 for a couple of weeks and this is really the first time i've had a chance to play with it. indoors though because it's pouring outside!! it seems that the lens is over exposing by about a stop, consistently. i've included 4 shots below to get your opinions. EV is set to zero. this is something else that has my head in a spin, i cant get my head around EV at all. i thought that adjusting this would compensate for my give ISO, f stop and shutter speed combination. But it doesn't.. it has no effect at all on the images. am i missing something? have i just had a complete brain fart? i was sure i had used EV before to adjust my exposure for a given shutter speed, etc. please can someone give me an explanation on EV. has anyone had any experience or ideas to why it should over expose. i was using matrix metering, ISO 200 and RAW.

first pair. f1.4 and f1.4 + 1 stop (1/13 and 1/25)
second pair. f16 and f16 + 1 stop (8 sec and 4 sec)

[coldrain]

Your post has some errors in the text which make it a bit hard to follow, but I think you shot the 1st and 3rd photo without any exposure compensation, and then the 2nd and 4th with -1 exposure compensation?

The 1st and 3rd are noticeably lighter!
So... what don't you get with exposure compensation?

And about over exposure (you mentioned that)... which photo do you find over exposed?

A camera (including yours) can NOT know what you are pointing it at. All it can do is judge how much light reaches its sensors. And then they pretend the overal subject or scene would be a mid tone, and the adjust the exposure to that, making what it thinks is the subject a mid tone. So, with a very dark subject or scene, the camera will take a LONGER exposure time, and with a lighter subject or scene the camera will take a SHORTER exposure.
The camera can not know what is right, it can just take an "educated" guess.
Most photos never are "correctly" exposed, but most are not so badly exposed that we actually notice it. Our vision is quite forgiving and adaptive. For the right exposure, or the exposure you are after, you have to start and learn more about how to judge/measure what exposure will give you your desired results.

I do not see the over exposure you mention, maybe you mean that the light on the knob is very bright? But the rest of the scene is very dark.

[Prospero]

The images on the left indeed look quite bright. Most Nikon dSLRs seem to have a tendency to overexpose, so that is what you might have experienced here.

The Exif of your images tells you you used manual exposure. In that case the Exposure Compensation doesn't do anything.

The Exposure compensation only works in shutterspeed priority, apperture priority and program modes. In the shutterspeed priority mode it allows you to use a larger or smaller aperture than that proposed by the camera meter and in aperture priority it does that with the shutterspeed.
In program mode it does a bit of both.

In manual mode you have picked both the shutterspeed and the apperture yourself, which means that the camera has no exposure variables it can control.

I assume here that auto iso is off and so that the camera is not in control of the ISO. I never use auto iso myself, so I wouldn't know if exposure compensation has any effect on the the auto iso.

[Tony_V]

I assume here that auto iso is off and so that the camera is not in control of the ISO. I never use auto iso myself, so I wouldn't know if exposure compensation has any effect on the the auto iso.

In manual mode, exposure compensation will affect the ISO if you have is set to auto ISO (at least it does on my D-80). I found this out the hard way...

Tony

[AllanC]

thanks guys. no i dont have ISO set to auto. i think prospero has hit the nail on the head. i kinda knew that my camera over exposed by a little, maybe 1/3 of a stop but i was just a bit shocked to find the images so bright. to me the wooden knob with the highlights on it is "blown". i guess it's just something i'll have to bare in mind when i'm using this lens indoors. i'll need to go out and do some test shots outside. the room i shot the pictures in was very dark. i'll let you know what the outside one's are like. i appreciate the replies, all of you.

thanks for the EV explanation as well prospero... :o what an ass i am!!!

[Tony_V]

Adding to what coldrain posted above, the camera will always try to expose so that the entire image averages out to mid-tone. I read a tutorial on this. In the article they took 3 test shots; 1 gray card, 1 white card and 1 black card. Interesting they all turned out gray. The camera over exposed the black card to make it mid-tone average 'gray' and under exposed the white card to do the same. The point is if your scene has mostly dark in it the camera will most likely over expose it and if it is mostly light it will underexpose. Like coldrain said you have to learn how to make the educated guess of what exposure compensation to dial in.

Tony

[aparmley]

When someone says that they knew or know that (their) DLSRs over expose a little is this a conclusion that was made after shooting hundreds of tests shots to confirm that every shoot they have to dial in a little - EV to get an exposure they like? Or is it simply that they are not analyzing the scene + meter mode to better understand why the camera is picking its exposure. I find my D80 to be very accurate with its Meter. Most of the time I find the exposure to be off is because there is an element in the scene which the camera is weighting more than say my subject. Part of learning photography is noticing what elements in a scene the camera will give more importance to when determing the exposure settings based on the metering mode selected.

In the scene above I'm picturing this bed post is being lit by window light, and the background is in the shadows. Since the background makes up a majority of the photo the camera is going to try to expose the background properly, thus over exposing what is lit by the window light.

Have you tried shooting this this shot with center AF spot focus on and use spot metering? I bet the exposure gets closer to the one you were hoping for - give it a try. If you don't have spot metering just put your camera in P mode, make sure no EV is dialed in and move your camera in really close to the post and take a meter (half press of the shutter) right, your too close to focus but you aren't to close to meter. Now note the settings, back out dial those settings in and take the photo? How'd we do? Further considerations are that cameras will overexpose dark items, it will underexpose light items all in trying to make everything a medium grey like Tony_V spoke about.